Carrier for pneumatic dispatch tube apparatus



I Jan. 4, 1938. 1 T, NEEDHAM 2,104,093

CARRIER FOR vPNEUMATIC DISPATCH TUBE APPARATUS Filed sept, 23, 19352sheets-sheet 1 ATTORNEYS Jan. 4, 1938. J. T. NEEDHAM 2,104,093

CARRIERFOR PNEUMATICI DISPATCH TUBE APPARATUS v Filed sept. 2:5, 1955 2Sheets-sheet 2 n l l I I l A I T `INVENTOR BYE Q 'i ATTORNEYS PatentedJan. 4, 1938 UNITED STATES y 42,104,093y PATENT OFFICE CARRIER. FORPNEUMATIG DISPATCH TUBE APPARATUS John Needham, North Plainfield, N. J.,as-

signor to Lamson General Conveyors, Limited, Montreal, Quebec, Canada, acorporation of Canada Application September 23, 1935, Serial No. 41,642

18 Claims.

rier with the two -shells arranged in open posi-r tion;

Fig. 2 a transverse sectional view of one head of the carrier taken onthe line 2-2 of Fig. 1;

Fig. 3 a transverse sectional view of the carrier body taken on the line3-3 of Fig. 1;

Fig. 4 a detail transverse Sectio-nal .view of av l5 portion of one headof the carrier taken on the line 4--4 of Fig. 1;

Fig. 5 a detail View of a portion of the accelerating washer carried bythe head of the outer shell;

Fig. 6 a side elevation of the inner shell partly formed, a part beingbroken away;

Fig. 7 a view similar to Fig. 6 of the outer shell;

Fig. 8 a detail side elevationrpartly in section of thek metal cup whichis secured to and closes the outer end of the inner shell;

Fig. 9 a view similar to Fig. 8 o-f the cup which is secured to andcloses the outerend of the outer shell;

Q Fig. 10 a side elevation of the lock hinge by means of which the twoshells are rotatively locked together;

Fig. l1 a view of the blank from.which the inner cylindrical shell isformed;

3.-). Fig. 12 a View of the blank from which the outer shell is formed;

Fig. 13 a detail View of the felt'disk from which the felt covering forthe heads is formed; and v Fig. 14 a detail View of a pair of dies forshaping the felt disk to t the carrier heads.

The carrier comprises a tubular cylindrical outer shell I and a similarinner shell 2 closely fitted in the outer shell, the two shells when in-45, ,fteriitted forming a tubular cylindrical container body. The shellsare made of sheet metal, preferably steel of the desired thickness. Y

The inner shell 2 is formed from a iiat blank 3 cut out along itslongitudinal edges as at 4 to 5r) Vform the large entrance aperture 5 inthe iinished being spaced suitable distances apart. distance inwardlyfrom prongs 1 is formed a series of stamped out tongues 8. These tongues8 are .arranged across the entire width of the blank and a shortdistance inwardly from the prongs 1 and extend in a direction oppositethe prongs 1,

A short that is to say the free ends of the tongues 8 are inward of theend of the blank.

The blank 3 is bent by suitable means` into cylindrical form and theabutting edges 9 and I0 are temporarily or permanently connectedtogether to hold the shell to form. The end of the cylindrical shellopposite the prongs 'I is then slightly reduced in diameter as at II bya suitable operation. The end of this reduced portion is then bent toformA the ange I2, said flange being turned outwardly, and compressedagainst a ringl3,y said ring serving to rigidly hold the shell in.cylindrical form. The reduction in diameter of the shell to form thereduced portion II results in the formation of aninternal shoulder orabutment Ila. The formation of the annular ange I2 at the end of theshell 2 results in an internal abutment or shoulder |25. These internalabutments |Ia and I2a cooperate with the means for retaining the twoshells in assembled position, as will be more fully hereinafterdescribed. Y

In the reduced portion at the inner end of the shell 2, outwardlypressed abutments 2| and 2|a are formed at diametrically oppositepoints. The abutment 2| is adapted to cooperate with inwardly pressedabutments formed on the outer shell, as will be hereinafterdescribed.The inner sides of the abutments 2| and 2 |a form inwardly facingpockets 2|b which are adapted to receive the spring locking means tolock the two ,shells in closed position, as Will be hereinafterdescribed.

The body. of the shell is slightly reduced in diameter by a suitableoperation to form a slight shoulder I4 close to the free ends of thetongues 8. The free ends of the tongues 8 are bent outwardly, as shownclearly in Fig. 6, so that the said tongues incline with respect to theaxis of the shell. The prongs I are on that end of the blank which formsthe outer end of the iinished shell. To close the outer end of the shell2 a sheet metal end cup' Ill` is provided. This cup is formed of a sheetmetal stamping and comprises the central well IS, considerably smallerin di ameter than the body of the shell, and the circular portion Ilformed with an annular flange I8 around the edge` thereof, said flangeand the annular wall of the well I5 extending from the same side of theannular portion Il and Vin the same direction. The portion I'I is formedwith an annularl series of apertures I9 which are adapted to receive theprongs 'I on the end of the shell. Inwardly of the apertures I9 a seriesof tongues 2D are stamped out of the portion I1,

Vshell as shown clearly in Fig. '2.

tance inwardly of the tongues 2l an annularY said tongues extendingoutwardly from the cup margin at an angle with respect Vto the axis ofthe cup. The prongs i after passing through the apertures i9 are bentover and rmly clinched to the outerside of the flange I8, asV

shown clearly in Fig. 1.

The cup I serves to close the outer end of the 1 margins of thesev cutout portions are folded inwardly to form the flanges around the entranceapertures, as shown in Figs. 1 and 3. By folding the'margnal edges ofthe cut out portions, as described, the entrance aperture is'prof videdwith a-sinooth'nishing welt around its edge. The entrance aperture inthe outer shell is of such dimensions and is so located in the shellthat when the inner and outer shells are placed in position to fullyopen the entrance aperture the margin of the-aperture 25A extendsslightly beyond the margin of the aperture 5 of the inner shell exceptat the extreme ends of the apertures where the margins coincide, asshown in Figs. 1 andV 3. The entrance apertures in both shells areapproximately of the same dimensions. This permits of the maximumdimensions of the entrance aperture with the removal of the least amountof metal from the outer shell. This isV of advantage inthat the outershell is thereby made slightly stronger and in the fullyV openedpositions of the two shells the margin of its aperture extends beyondthe margin ci the aperture of the inner shell, except at the ends of theapertures, and thereby to a certain extent protects the inner shell.V

VvThe blank 22, at one end,'is formed with a series of longitudinallyextending prongs25, said series of prongs extending along the entireedge of the blank and being spaced suitable distances apart. A shortdistance Vinwardly from the prongs 23 is formed a seriesY of stamped outtongues 2l. These tongues 27 are. arranged across the entire width ofthe blank and a short distance inwardly from the prongs 26 and extend ina direction opposite to the prongs 26, that is to say the free ends ofthe tongues 21 are inward of the end of the blank.

The blank 22 is bent by suitable means into I cylindrical form and theabutting edges 28 and 29 are temporarily or permanently connectedtogether to hold the shell in its cylindrical form.

The end of the cylindrical shell, opposite theV prongs 25, is forcedoutwardly to form the outwardly extending annular ilange 30, said flangebeing located at the inner open end of the shell. The tongues 2l areforced outwardly to a position at an angle with respect to the axis ofthe A slight disoutwardly extending flange 3i is formed in the body orthe shell I. Inwardly pressed abutments 32 and 32a are formed in thebody of the shell adjacent the tongues y2l and at properly spaced pointsaround the shell, as shown in Figs. 2 and 7. These abutment-s 32 and 32acoop- The Vcup also reinforcesV erate with abutment 2| on the innershell to serve as limiting stops for the rotation o1 the shells oneachother, abutment 32 stopping the ,shells in open position, as shownin Figs. 1 and 2, and abutment 32n stopping the shells in closed vposition.

To close the outer end of the shell I an end cup 33 is provided. Thiscup is formed of a sheet metal stamping and comprises the central well34 considerably smaller in diameter than the body of the shell and thecircular portion 35 formed with an annular flange 36 around the edgethereof, said flange and the annular wall of the well 34 extending fromthe same side of the circular portion 35 and in the same direction. Theportion 35 is formed with an annular series of apertures 3l which areadaptedto Vreceive the prongs V2li on the VVend ofthe shell I. Inwardlyof the apertures 3l a seriesof tongues 38 are stamped out of the portion35, said tongues extending outwardly from the cup margin at an anglewith respect to the axis of the cup. The prongs 26, after passingthrough the apertures 3l, are bent over and firmly clinched to the outerside of the ange 36, as shown clearly Vin Fig. l.

Around the flange 3B at the inner end of the outer shell is secured anannular clamping ange 39. This clamping flange reinforces the inner endof the shell I and serves to hold theshell in cylindrical form. The cup33 closes the outer end of the shell I, and forms the end wall of thenished shell, the well 34 forming an inwardly extending depression insaid end wall open to the exterior of the carrier. The cup alsoreinforces the shelland ensures its outer end remaining in cylindricalform. Y

The annular wall of the well 34 is provided with two apertures 49 atdiametrically opposite points to receive the ends of a retaining spring,and the said wall is also ormed'with'an aperture 40a to receive medialportion of the said retaining spring, as will be more fully hereinafterdescribed. The said wall is also formed with an aperture 4!)b whichserves to give access to a portion of a locking spring, which springserves to lock the two shells in open position, as will be more fullyhereinafter described.

When the two shells are assembled the-,well portion 34 of the cup 33extends into the inner shell through the end opening formed by the angei2, the said Well portion being approximately of the same diameter asthe said opening, as shown clearly in Fig. ,1, and the ange 39 onthe'inner end of the outer shell is only a slight distance from theshoulder I4 at the outer end of the inner shell. The reduced portion IIof the inner shell and the annular Wall of the well 34 form an annularclearance space to receive the means for yieldably locking the shells intheir closed position, and also the means for retaining the two shellsin assembled position against endwise displacement. To hold the twoshells together and to permitv of the rotation of said shells to openand closed positions a retaining ring 4I is provi-ded. The internaldiameter of this ring is such that it ts around and receives Within itthe annular wall of the well 34 of the cup 33. The ring 4I is providedwith an annular flange 43 slightly larger in diameter than the flange42, the outer marginal edge of the flange 43 resting on the internalabutmenti I e. of the lnner'shell. The inner surface of the flange 43`isflush, or substantially so, with the inner 46 in the retaining ring 4|.

inner shell and the annular wall of the well 34.

shell comprises a retaining spring 44.- This spring is arranged in thewell 34 so that it may be inserted and removed through the cup 33 and isalways accessible from the exterior of the carrier. The ends of thisretaining spring are bent outwardly to form the retaining fingers 45which extend radially outwardly as vshown in Fig. 2. VThese retainingfingers extend through the apertures 40 in the annular wall of the well34 and also extend outwardly through apertures The spring 44, midway itsends is bent outwardly to form a loop 41 which extends radiallyoutwardly through the apertures 4Q- in the annular wall of the well 34and through an aperture 48 in the ring 4|. The retaining spring 44therefore connects the cup 33 to the ring 4| and said ring is free torotate with the outer shell. The flange 42 resting on the abutment |2aholds the two shells together against endwise separating movement. Theflange 43 assists in retaining the shells against endwise separatingmovement by engaging the shoulder or abutment IfL and also serves toclose the annular clearance chamber, as hereinbefore described, andprevents the contents of the carrier becoming caught or jammed in saidchamber. It also covers and protects the retaining spring. Y

Whenever it is desired to separate the two shells the retaining spring44 is manipulated by any suitable means inserted into the well 34 of thecup 33 to withdraw the retaining fingers from the apertures 4E! and 45.The spring loop 41 mayl then be withdrawn from apertures 402*V and 48.-To lock the shells in their closed position a locking spring 49 isarranged in the channel formed by the ianges 42 and 43 of the ring 4|.This locking spring is provided withan inwardly extending loop U midwayits ends, said loop extending through a flanged aperture5| in the ring4| and also through the aperture 40h of the curved locking detents 52.The arms of the spring 49 between the loop 53- and the locking detents52 tend to spring outwardly and to maintain the locking detents againstthe inner surface of the reduced portion I'of the inner shell, as shownclearly in Fig. 2. The locking spring with its Idetents 52 is so placedwith respect to the locking sockets 2|b of the inner shell that when theabutment 2| engages the abutment 32a the yJdetents 52 will snap intosaid socket 2|b and hold the two shells locked in closed position. Aslight pressure ony the shells tending to rotate them to open positionwill force the spring detents 52 out of the sockets 2lb and permits theshells to be rotated to open position.

When it is desired to separate the two shells and the retaining spring44 has been removed, it is necessary to force the loop 50 outwardly asufficient distance to free it from the annular Wall of the well 34.This may readily `be done The ends of the locking spring 49` are bowedvoutwardly to form the outwardly because the loop 56 is accessible fromthe exterior of the carrier through the open end oi the well 34, asshown clearly in Fig. l. One shell may then be withdrawn endwise` fromthe other. The looking spring 43 serves to lock the two shells in closedposition. It does not lock the two shells in open position, as isclearly shown in Fig.'2 oi the drawings.

When assembling the two shells the loop 5@ of f the locking spring mustbe brought into register with the aperture 43h of the cup 33. This willbring into register apertures 4B and 46 and apertures 4Q@ and 48. Theloop 47 of the retaining spring 44 may then be passed outwardly throughthe registering apertures ida and 48, and the retaining fingers 45 ofsaid spring may be passed through the registering apertures 4!) and 4S.The aperture 401 of the cup 33 is so located with respect to theabutments 32 and 32EL of the outer shell l, that when the loop 53 of thelocking spring extends into aperture 4Gb the spring den tents 52 will beso located that when the abutment 2l of the inner shell engages theabutment 32a of the outer shell, the spring detents will snap into thelocking sockets 2 lb of the inner shell.

Buier heads are secured to the outer ends of both the inner and outershells. These heads are of the same construction and therefore a description of one will be suicient. Under the tongues 8 of the inner shell isplaced an annular band or ring or" rubber 54. This ring is inclined onits outer surface to t snugly under the tongues 8.

Under the tongues 2li is arranged an annular band or ring of rubber,said band 'being in clined on its outer face to conform to theinclination of the tongues 2li and to iit snugly between said lugs andthe portion Il of the cup I5. The 'rubber bands 54 and 55 are suitablysecured in position by cement, or by Vulcanization or otherwise.Surrounding and enclosing the outer endrof the carrier and fittingclosely over the tongues 8 and 2t is a re-inforcing buffer head portion5t of rubber. This buffer head portion is substantially right angular incross section with the outer surface thereof rounded, asv shown clearlyin Fig. l. This head portion 5t is a ringlike structure having anopening oi substantially the same diameter as the internal diameter ofthe well portion of the end cup to which it is secured. This headportion 5t is preferably molded to form and is then cemented orvulcanized or otherwise secured in position. The rubber rings A54 and 55are intimately united with the head portion 55 between the tongues bycement or vulcanization o-r otherwise so that the head portion issecurely anchored to the tongues 8 and 2li, and to the exterior of theshell.

The outer surface of the head 55 is preferably enclosed within a rfeltcovering 5l. This felt covering is preferably made from a ring 58 ofsheet felt of the desired thickness. The ring 58 is saturated with waterand is then placed between two dies and pressed to the proper form toaccurately t the rounded exterior surface of the head portion 55. InFig. 14 is illustrated a pair of dies suitable for pressing the ring 58to proper form. When the pressed ring has dried it is permanently inshape to be fitted to the surface or" the head 55 and may be securedthereto by cement, Vulcanization or otherwise. As shown in Fig. 1 accessmay be had to the interior of the wells of the end cups through thecentral opening in the head 5S and the felt covering ring 5l. Anaccelerating washer 59 of rubber, or other suitable flexible material,is permanently secured to the flat transverse edge of the head portion5S of the inner shell, and said washer is held in place by means of ametal ring @il secured to the inner face of said washer and betweenwhich and the head the washer is permanently held. The washer 5a lies ina plane transverse tothe axis of the shell. When the two shells areassembled the nished flange 39 of the outer shell 'contacts'slightlywith the metal washer till; as shown clearly in Fig. Vl.

A removable accelerating washer 6l is secured to the transverse at edgeof the head portion 56 of the outer shell. This washer 6l is formed oi aring oi comparatively stiff but ilexible ma-Y Iterial which is cut outaround its inner margin as at 62 to reduce the stiness of the materialand to permit it to be expanded sufficiently to pass over the flanges 3%and of the outer shell. Secured to the flat sides of the ring El laretwo comparatively soft exible rubber rings 63, said rings covering thecut-out portions 62. The rings 63 are sufficiently flexible to permitthe composite ring to be expanded suciently to pass over the flanges 39and 3l. The composite :washer (5!*63 iits between the flange 3l and theadjacent ilat face oi' the head portion Eli and lies in a planetransverse of the axis oi the shell.

The washer El may be readily removed when it becomes worn and a newwasher placed in position on the head of the outer shell. lf desired thering B3 contacting with the head portion 53 may be cemented or otherwisesecured thereto.

From the foregoing it is manifest that all the Y metal parts of thecarrier may be made of 'stamped sheet metal and that these parts Vmay bereadily stamped or otherwise shaped to final form. The parts forming thebuiler heads may belreadily molded in proper form and Vthen cemented orotherwise secured to the carrier shell. The result oi such constructionis that the carrier may be cheaply and quickly made, and will be oisturdy construction to withstand therough usage to which carriers ofthis type are subjected in use.

What I claim is:

l. A carrier comprising a pair of tubular shells tted one withinV theother and each having an entrance opening in its side, said shells beingrelatively rotated to bring said openings into and out of register witheach other to open and close the carrier, characterized in that theinner shell has an inwardly extending annular transverse abutment at itsinner end, aY retaining ring withinY the inner shell and in engagementwith the said annular flange, and releasable retaining means extendingthrough the outer shell'and engaging the retaining ring to hold the twoshells against endwise displacement, said releasable retaining meansbeing accessible from the exterior of the carrier.

2. A carrier comprising a pair of tubular shells tted one within theother and each having an entrance opening in its side, said shells beingrelatively rotatable to bring saidopenings into and out or" registerwith each other to open and close the carrier, characterized in that aretaining ring is within the inner shell and in engagement with acooperating part of the inner shell,

and releasable retaining Ymeans extends throughV the outer shell andengages the retaining ring to hold the retaining ring and the two shellsagainst endwise displacement, said releasable retaining means beingaccessible from the exterior or" the carrier.

3. A carrier comprising a pair of tubular shells tted one Within theother and each having an entrance opening in its side, said shells beingrelatively rotatable to bring said openings into and out of registerwith each other to open and close the carrier, characterized in thattheV outer shell has an end wall centrally depressed inwardly to provideit with -an'annular wall portion, and the adjacent end portion of theinner shell is peripherally contracted to provide the shell with atransverse, annular internal shoulder and with an annular wallconcentric with and spaced from said annular portion of the end wall,and a shell-retaining ring is interposed between said annular walls andhas a ange bearing against said internal shoulder of the inner shell forthepurpose set forth, and said ring and the annular portion of the endwall have registering apertures, and means extend through said apertureto hold the retaining ring and the inner shell to the outer shellagainst endwise displacement, and said holding means are shiftable torelease position'from the exterior of the carrier through said enddepression. Y

4. A carrier according to claim 3, characterized in that said holdingmeans comprises a bowed retaining spring 'arranged in the end depressionand having a medial locking projection extending through said aperturesto lock the retaining ring in the outer-shell to thereby hold theretaining ring and the inner shell to the outer shell against endwisedisplacement, said retaining spring being'shiftable to release positionfrom the exterior of the carrier through said end depression.

5. A carrier comprising a pair of tubular shells tted one Within theother and each having an entrance opening in its side, said shells beingrelatively rotatable Vto bring said openings into and out of registertol open and close the carrier, characterized inV thatV said shells havea clearance space therebetween at one point in their length andextending around theirraxis of rotation, and the inner shell is pressedoutward at one point on its periphery to form a recess and to form astop projection in said clearance space, and the outer shell is pressedinward at one point on-its periphery to form an integral stop projectionin said spacercooperable with said rst projection to limit relativerotation of the shells, and yieldable snapY locking means are providedto engage in said recess to yieldably resist relative rotation of theshells in a direction to separate said stops.

6. A carrier comprising a pair of tubular shells tted one within theother and earchV having an entrance opening in its side, said shellsbeing relatively rotatable to bring said openings'into and out ofregister to open and close the carrier, characterized in that the shellshave a clearance space therebetween at a point adjacent one end of thecarrier and extending around their-axis of rotation, and the inner shellis pressed outwardly at two diametrically opposite points on itsperipheryto form inwardly facing recesses and outwardly extending stopabutments in said clearance space, and the outer shell is pressed Yinwardly at one point on its periphery to form warclly facing recessesin the inner shell to yieldably resist relative rotation of the shellsin a direction to separate said stop abutments to open the carrier.

7. A carrier comprising a pair of tubular shells fitted one within` theother and each having an entrance opening in its side, said shells beingrelatively rotatableto bring said openings into and out of register toopen and close the carrier, characterized in that the shells have aclearance space therebetween at a point adjacent one end of the carrierand extending around their axis of rotation, and the inner shell ispressed outwardly at two' diametrically opposite points on its peripheryto form inwardly facing recesses and outwardly extending stop abutmentsin said clearance space, and the outer shell is pressed inwardly at oneApoint on its periphery to form an inwardly extending stop abutmentprojecting into said space and cooperable with one of the abutments onthe inner shell to' limit relative rotation of the shells to closedposition, and a retaining ring is arranged in said clearance space andin -engagement with the inner shell, and two yieldable snap lockingdetents are provided in said clearance space and releasably connected tothe outer shell and the retaining ring to lock the two shells againstend-wise displacement, and

said detents being arranged to` snap into* the two' inwardly facingrecesses in the inner shell to yieldably resist relative rotation of theshells in a direction to separate said stop abutments and to open thecarrier.

8. A carrier according to claim 3, characterized in that said holdingmeans comprises a bowed retaining spring arranged in said enddepression, the spring has a medial locking projection extending throughsaid apertures to lock the retaining ring in the outer shell to therebyhold the retaining ring and the inner shell to the outer shell againstendwiseV displacement, said spring also has retaining fingers extendingapproximately radially of the carrier, .the annular wall of saiddepression and the annular wall of the retaining ring have registeringapertures into which said fingers snap, and said retaining spring isshiftable to release position from the exterior of the carrier at saiddepression.

9. A carrier comprising a pair of tubular shells fitted one within theother and each having an entrance opening in its side, said shells beingrelatively rotatable to bring said openings into and out of registerwith each other to open and close the. carrier, characterized in thatsaid shells have a clearance space therebetween at a point in theirlength and extending around their axis of rotation, a retaining abutmentelement is disposed in said space, one of the shells has an abutment toengage said abutment element, a fastening element extends through theother shell and releasably engages said abutment element to hold it inplace, said abutment element, said shell abutment and said fasteningelement are constructed and arranged to cooperate to hold together theshells against relative endwise displacement, and the fastening elementis accessible from the exterior of the carrier for release of saidelement to permit separation of the shells.

l0. A carrier according to claim 9, characterized in that the. carrierparts are constructed and arranged to permit endwise withdrawal of theinner shell and the said retaining' abutment element from the outershell upon release of said fastening means.

11. A carrier comprising a pair of tubular shells fitted one within theother and each having an entrance opening in its side, said shells beingrelatively rotatable to bring said openings into and outof register witheach other to open and close the carrier, characterized in that theouter shell has an outer end wall formed with a depressed portionforming a recess opening outside of the carrier and a protuberanceWithin the carrier and having a space around its periphery within thecarrier, a retaining abutment element is disposed in said space, anabutment is borne by the inner shell within the carrier and isengageable by said abutment element' a fastening means penetrates saiddepressed end wall portion and releasably engages said abutment elementto hold it in place, said abutment element, said inner iell abutmentandsaid fastening means cooperate to hold the shells together againstrelative endwise displacement, and said fastening means is accessiblefor release thereof at said end recess for separation of the sheils.

12. A carrier according to claim 1l, characterized inthat said retainingabutment element is annular in shape and surrounds the said in-l wardprotuberance of the end wall of the outer shell and is substantiallyflush with said protuberance to. form therewith a substantiallycontinuous end wall for the containing space of the carrier.

13. A carrier according to claim 11, characterized in that saidretaining abutment element is in the form of a ring surrounding the saidinward protuberance of the end wall of the outer shell, the adacent endportion of the inner shell is reduced in diameter to afford between theinnerl and outer shells a space extending around their axis of rotation,and the shells have stops Within said space to limit relative rotationof the shells.

14. A carrier according to claim 11, characterized in that the endportion of the inner shell adjacent to said depressed end wall of theouter shell is reduced in -diameter to afford a space between the shellsextending around their axis of rotation, the shells have stops withinsaid space to limit relative rotation of the shells, andthe saidreleasable fastening means embodies resilient locking means cocperablewith the inner shell for yieldable snap locking of the shells in closedrelation.

15. A carrier according to claim 1l, characterized in that the saidreleasable fastening means embodies resilient locking means cooperablewith the inner shell for yieldable snap locking of the shells in closedrelation.

16. A carrier according' to claim 11, characterized in that the saidreleasabie fastening means comprises a resilient element normally heldby its resilience in retaining' engagement with the said retainingabutment element and adapted to be forcibly retracted from the abutmentelement for release of the latter and separation of the shells.

17. A carrier according to claim 11, characterized in that the carrierparts are constructed and arranged to permit endwise withdrawal of theinner shell and the said retaining abutment element from the outer shellin a direction away from said end wall of the outer shell upon releaseof said fastening means.

18. A carrier according to claim 11, characteriz-ed in that the said endof the outer shell bears an annular bufferhead whose central aperture isin register with the said end recess of the shell for entry to therecess to release the said fastening means, and said buffer head issecured to the outer shell independently of the inner shell.

JOHN T. NEEDHAM.

